The Klingons have been humiliated by asking the Federation for help, so a growing number reach back to antiquity, embracing a more "simple" time, when Klingons were realKlingons! Maybe there was a resurgence of the following of Khaless, as he's hardly mentioned until TNG.

It would also inadvertently explain why Gowron said women could not be on the High Council, when Azetbur was in charge in Star Trek VI. "A woman ruled the High Council, then we ended up crawling on our hands and knees begging for for help from the Federation!"